un·​treat·​ed | \ ˌən-ˈtrē-təd How to pronounce untreated (audio) \

Definition of untreated

: not treated untreated wastewater especially : not improved or controlled medically an untreated case of pneumonia untreated diabetic patients

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Synonyms & Antonyms for untreated


crude, native, natural, raw, rude, undressed, unprocessed, unrefined


dressed, processed, refined, treated

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Examples of untreated in a Sentence

Recent Examples on the Web

Preeclampsia affects black women at rates 60% higher than white women and if left untreated can lead to complications like stroke and kidney failure in the mom and premature birth or death for the baby. Leta Shy, SELF, "Allyson Felix Wants to Save Black Mothers," 30 July 2019 Nearly 37 million people are living with HIV, according to UNAIDS, which if left untreated can develop into AIDS. N'dea Yancey-bragg, USA TODAY, "Researchers have eliminated HIV in mice for the first time. Is a cure for humans next?," 2 July 2019 If left untreated, the infection can spread to joints, the heart and the nervous system, according to the CDC. Lawrence Andrea, Milwaukee Journal Sentinel, "Lawmakers want to combat Lyme disease with more signs, insect repellent in public parks," 24 June 2019 By hewing to a physiological definition of infertility, Pellittieri’s insurance policy would leave her untreated. Anna Louie Sussman, The New Yorker, "The Case for Redefining Infertility," 18 June 2019 To that effect, experts have for some years been encouraging homeowners to leave their grasses untreated and enrich lawns with flowering plants, thereby creating a safe and diverse habitat for bees. Brigit Katz, Smithsonian, "Minnesota Will Pay Residents to Grow Bee-Friendly Lawns," 17 June 2019 Ayanna was born with an eye condition called cherry eye, which can be harmful to the dog’s sight when left untreated but is easily fixed with surgery. Maria Lovato, BostonGlobe.com, "Three pit bull mix puppies found in Jamaica Plain cemetery," 24 July 2019 If left untreated, the infection could eat away at the tissue and possibly enter her blood stream, Horney said. San Diego Union-Tribune, "Street medicine team makes housecalls to homeless," 17 July 2019 At a House Oversight Committee hearing earlier this week, asylum seeker Yazmin Juarez testified on the death of her 19-month-old child, whose illness was untreated while they were held in ICE custody. Erin Corbett, Fortune, "Trump Family Separation Policy ‘More Harmful’ Than First Thought: House Report," 12 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'untreated.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of untreated

15th century, in the meaning defined above

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Statistics for untreated

Last Updated

10 Aug 2019

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Time Traveler for untreated

The first known use of untreated was in the 15th century

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More Definitions for untreated



English Language Learners Definition of untreated

: not getting medical care : without medical treatment
: not made better or safer by being treated with a chemical or other substance


un·​treat·​ed | \ -ˈtrēt-əd How to pronounce untreated (audio) \

Medical Definition of untreated

: not subjected to treatment an untreated disease

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More from Merriam-Webster on untreated

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Spanish Central: Translation of untreated

Nglish: Translation of untreated for Spanish Speakers

Comments on untreated

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to move or obtain by small maneuvers

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